This invention relates to tactile display devices and methods, and, more particularly, relates to such devices and methods wherein a tactile display is readily reconfigurable.
One of the potential benefits of advances in computer and related technologies is the prospect for improved accessibility to information services for the handicapped, particularly electronically stored or transmitted information. For the blind and vision impaired, work has been done on improved accessibility by special adaptations to visual displays, by voice-based systems (voice output and in some cases voice input), and by touch-based devices. Each of these approaches is particularly useful for certain applications, and serves a certain part of the population of users.
The most common implementation for a touch-based computer-driven display is the refreshable Braille reader. This is a device which produces a pattern of raised dots in the six (or eight) dot cells that represent Braille characters (see U.S. Pat. Nos. 6,109,922 and 4,551,102, for example). Often, the dots are controlled by actuators (typically one per dot in each cell), and can be individually set to change the Braille characters being displayed on each Braille cell. Typically, a single line of Braille is made available, ranging from a relatively short line for a portable device, to 80 characters or more for a device built into a desktop keyboard. These devices produce a usable, refreshable Braille display, but suffer the drawbacks of extremely high cost and mechanical unreliability (due in large part to the great number of mechanical components). Cost and reliability issues have thus hindered the expanded use of Braille as a computer interface.
Some heretofore known full-scale Braille readers may contain hundreds of actuators. Since the traditional method of constructing a refreshable Braille display producing a linear array of Braille cells requires a separate actuator for every dot of every cell in the display, an 80 cell display of 8-dot Braille (per cell) would require 640 actuators. Actuators are the primary expense in traditional Braille displays, and also represent the most likely source of introduced unreliability into the system.
Other heretofore known systems rely on complex systems of magnets (electromagnets and permanent magnets) to move and retain Braille characters. Such systems have not always been found to produce reliable results and/or are expensive to manufacture given the need for specificity and isolation of the magnetic effects from one Braille dot to the next.
Improvement in such devices producing computer-refreshable Braille text for tactile reading by the blind and visually impaired could thus be utilized thereby broadening accessibility to computer services such as electronic books, e-mail and other network access, and general computer use. Improvements in cost and mechanical reliability must be attained in order to facilitate more widespread use of refreshable Braille devices. Mechanical simplicity over existing refreshable Braille devices, while providing much of their functionality as well as additional features, would be desirable for users while greatly lowering cost and improving reliability in comparison to existing systems. Moreover, such systems should be easily reversible and searchable (forward and back) so that a user may review Braille text as necessary and desired by the user.
This invention provides apparatus and methods for producing refreshable tactile display, in particular refreshable Braille text that can be streamed at a display surface in either forward or backward order by utilizing bi-directional relative movement of components of the apparatus. The apparatus can be produced at a great reduction in cost of manufacture over heretofore known devices while yet realizing greatly increased mechanical reliability and simplicity.
The refreshable Braille reader broadly includes a display assembly having an outer surface with a plurality of openings therethrough, the openings arranged in rows. Pins are mounted in the openings and are movable therein.
The actuating means preferably includes at least a first actuator assembly having actuators at least equal in number to number of the rows of openings in the display assembly surface. Each actuator includes a driver, a shaft selectively extendible and retractable by the driver and first and second contact tips at the shaft. The actuators are positioned so that the first contact tip can selectively contact the first ends of the pins and the second contact tip can selectively contact the opposite ends of the pins.
The actuating means preferably includes at least a first actuator assembly having actuators at least equal in number to number of the rows of openings in the display assembly surface. Each the actuator includes a driver, a shaft selectively extendible and retractable by the driver and first and second contact tips at the shaft. The actuators are positioned so that the first contact tip can selectively contact the first ends of the pins and the second contact tip can selectively contact the opposite ends of the pins.
In the now preferred embodiment of the refreshable Braille reader, a cylinder connected with a motor for rotation thereof in either of two directions is utilized. The cylinder has a cylindrical outer surface a part of which defines a tactile display area and a cylindrical inner surface, the openings extending between the surfaces.
The actuators are statically positioned, are at least equal in number to the rows of openings through the cylinder, and are configured so that the pins are selectively contactable at either of their ends by different ones of the actuators during cylinder rotation in either of the two directions, thereby streaming Braille text across the display area in either forward or backward order depending upon selected direction of cylinder rotation. Controls are provided allowing user selection at least of direction of rotation of the cylinder.
In one embodiment first and second sets of actuators, each set having actuators at least equal in number to number of the rows of the openings, are provided, the first actuator set positioned at one side of the tactile display area and the second actuator set positioned at an opposite side of the tactile display area. The first actuator set selectively causes controlled pin movement in the openings for steaming Braille text in the forward order and the second actuator set causes controlled pin movement in the openings for streaming Braille text in the backward order.
The method for streaming Braille text in either forward or backward order at a display area of this invention includes the steps of effecting relative movement in either of two directions between a station and a display surface and selectively activating actuators at the station while effecting the relative movement in a first of the two directions to set pins at selected positions relative to the display surface by contact with the pins. Relative movement in either the first or a second of the two directions is continually effected to selectively reset the pins at selected positions relative to the display surface by selectively activating the actuators at the station to cause contact with the pins.
The implementation of the apparatus of this invention embodied for streaming of Braille text at a display surface and characterized as a rotating cylinder refreshable Braille reader would produce computer-refreshable Braille text for tactile reading by the blind and visually impaired. This implementation will improve accessibility to computer services such as electronic books, e-mail and other network access, and general computer use. The apparatus is designed to be mechanically simpler than existing refreshable Braille reader devices, while providing much of their functionality as well as additional features. The design of this apparatus allows for greatly lowered cost and improved reliability in comparison to existing systems and can be implemented in such a way as to provide refreshable Braille text to the user from a typical reading rate of 60 to 125 words per minute up to a high reading rate of 250 words per minute and in either forward or backward text streams (i.e., forward or reverse cylinder rotation).
The rotating cylinder refreshable Braille reader of this invention addresses cost and reliability issues of heretofore known systems by greatly reducing the number of actuators utilized to set Braille text at a reading surface, from hundreds in heretofore known implementations, to as few as three or four (though as many as sixteen may be desirable) depending on the particular configuration. Instead of a static linear array of Braille cells that the user reads by moving one or more fingers along the line, the rotatable wheel Braille reader herein disclosed sets the Braille dots on the surface of a wheel or disk, which rotates under the user""s finger, giving the user the sensation of a line of static Braille text moving under the user""s finger. The Braille text on the wheel is refreshed as the wheel rotates, either in a repeating pattern around the wheel, or (using actuators internal or external to the wheel) at a specific point in the rotation of the wheel, setting a pattern of Braille dots on the wheel that are passively retained until they have passed under the reader""s finger, after which they may be erased and then rewritten in the next rotation.
The preferred embodiments of the reader apparatus of this invention use a passive pin displacement approach, which can be used as the basis for either an external or internal actuator stationed refreshable Braille display. It can also be adapted to a linear Braille display, to certain types of tactile graphic displays, and may be applicable for non-accessibility application. Multiple Braille cells (potentially a large number) may be deployed displaying a valid text stream to the user. Improved control, precision, reliability of the device, greater versatility of operation, rapid display, long useful service life for the device, and extremely low cost of manufacture compared to now known systems will be achieved. The apparatus of this invention also utilizes means for replacing substantially continuously powered actuators with passive position retention, thereby greatly lowering the cost of manufacture and operation of a Braille display in a robust and mechanically simple manner.
It is therefore an object of this invention to provide improved apparatus and methods for producing a refreshable tactile display.
It is another object of this invention to provide apparatus and methods for streaming a tactile display at a display area.
It is another object of this invention to provide apparatus and methods for producing refreshable Braille text that can be streamed at a display surface in either forward or backward order by utilizing bi-directional relative movement of components of the apparatus.
It is another object of this invention to provide improved tactile display apparatus producing computer-refreshable Braille text for reading by the blind and visually impaired to improve access to computer services such as electronic books, e-mail and other network access, and general computer use.
It is still another object of this invention to provide a refreshable Braille reader apparatus that is mechanically simple and reliable, compact, lower in cost, fast, and that provides improved control, precision, and versatility of operation including providing either forward or backward text streaming capability.
It is another object of this invention to provide a refreshable Braille reader including a display assembly having an outer surface, the surface having a plurality of openings therethrough with the openings arranged at the surface in rows, a plurality of pins having first and second ends, each one of the pins mounted in a different one of the openings and movable therein, and actuating means maintained at a station adjacent to the surface of the display assembly for moving the pins, the pins selectively contactable by the actuating means to move the pins in the openings so that the first ends of the pins are selectively raised from or not raised from the surface, at least one of the actuating means and the display assembly being movable relative to the other of the actuating means and the display assembly in either of two directions, the actuating means capable of causing controlled pin movement in the openings while relative movement occurs in either of the two directions.
It is still another object of this invention to provide a refreshable Braille reader including a cylinder connected with a motor for rotation thereof in either of two directions, the cylinder having a cylindrical outer surface a part of which defines a tactile display area and a cylindrical inner surface, the cylinder having a plurality of openings therethrough between the surfaces, the openings arranged in at least three endless rows, a plurality of pins having first and second ends, each one of the pins mounted in a different one of the openings and movable therein, static actuators at least equal in number to the rows of openings through the cylinder maintained at a station adjacent to the cylinder, the actuators positioned and configured so that the pins are selectively contactable at either of the ends by different ones of the actuators during cylinder rotation in either of the two directions so that the first ends of the pins are selectively positioned relative to the outer surface of the cylinder thereby streaming Braille text across the display area in either forward or backward order depending upon selected direction of cylinder rotation, and user controls allowing control at least of direction of rotation of the cylinder.
It is yet another object of this invention to provide a method for streaming Braille text in either forward or backward order at a display area including the steps of effecting relative movement in either of two directions between a station and a display surface, selectively activating actuators at the station while effecting the relative movement in a first of the two directions to set pins at selected positions relative to the display surface by contact with the pins, and effecting relative movement in either the first or a second of the two directions to selectively reset the pins at selected positions relative to the display surface by selectively activating the actuators at the station to cause contact with the pins.
With these and other objects in view, which will become apparent to one skilled in the art as the description proceeds, this invention resides in the novel construction, combination, arrangement of parts and method substantially as hereinafter described, and more particularly defined by the appended claims, it being understood that changes in the precise embodiment of the herein disclosed invention are meant to be included as come within the scope of the claims.